This paper investigates ways to explore the between frame correlation of shape information within the framework of an operationally rate-distortion (ORD) optimized coder. Contours are approximated both by connected se...
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This paper investigates ways to explore the between frame correlation of shape information within the framework of an operationally rate-distortion (ORD) optimized coder. Contours are approximated both by connected second-order spline segments, each defined by three consecutive control points, and by segments of the motion-compensated reference contours. Consecutive control points are then encoded predictively using angle and run temporal contests or by tracking the reference contour. We utilize a novel criterion for selecting global object motion vectors, which improves efficiency. The problem is formulated as Lagrangian minimization and solved using dynamic programming. Furthermore, we employ an iterative technique to remove dependency on a particular variable length code and jointly arrive at the ORD globally optimal solution and an optimized conditional parameter distribution.
In this paper, we propose a statistical learning-based approach to analyze the rate-distortion characteristics of MPEG-4 multiscale binary shape coding. We employ the polynomial kernel function and epsilon-Insensitive...
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In this paper, we propose a statistical learning-based approach to analyze the rate-distortion characteristics of MPEG-4 multiscale binary shape coding. We employ the polynomial kernel function and epsilon-Insensitive loss function for our support vector regression. To improve the accuracy of the estimation, rate and distortion related features are incorporated in the statistical learning framework. Our experimental results show that the proposed approach can achieve good performance, e.g., modelling the rate-distortion curves accurately.
This paper presents an efficient VLSI architecture design of MPEG-4 shape coding, which is the key technology for supporting the content-based functionality of the MPEG-4 Video standard. The real-time constraint of MP...
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This paper presents an efficient VLSI architecture design of MPEG-4 shape coding, which is the key technology for supporting the content-based functionality of the MPEG-4 Video standard. The real-time constraint of MPEG-4 shape coding leads to a heavy computational bottleneck on today's computer architectures. To overcome this problem, design analysis and optimization of MPEG-4 shape coding are addressed in this paper. By utilizing the RISC-based model, computational behaviors of the MPEG-4 shape coding tool are carefully examined and analyzed. The characteristic of a large amount of bit-level data processing and data transfer of MPEG-4 shape coding motivates us the optimization of bit-level data operations. Applying the data-flow optimization and data reuse,techniques, bit-level computation-efficient architectures, such as data-dispatch-based binary-shaped motion estimation, the delay-line model, and configurable context-based arithmetic coding, are designed to accelerate bit-level processing. These hardware blocks are integrated and scheduled in a very efficient data flow to achieve real-time performance for MPEG-4 CPL2 specification at 23.5-MHz clock rate. The system architecture is implemented using Verilog HDL and synthesized with a 0.35-mum four-layer CMOS standard library.
An optimal frame memory and data transfer scheme is proposed for MPEG-4 shape coding in embedded systems. The proposed alpha frame buffer scheme contains two approaches. First, a distributed tile-based memory organiza...
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An optimal frame memory and data transfer scheme is proposed for MPEG-4 shape coding in embedded systems. The proposed alpha frame buffer scheme contains two approaches. First, a distributed tile-based memory organization is used to efficiently support the time-varying size of alpha plane. Second, a compression scheme is used to reduce the number of memory access to and the size of the alpha frame memory. Under the criteria of MPEG-4 standard, the size of alpha frame memory can be reduced to 50% by introducing a small index table (2.73%-5.08% of the original frame memory size). A coarse assessment shows that the number of memory reference can be reduced to 56.25%. On the other hand, the proposed data transfer scheme combines the run length coding and addressing mode to reduce average data transfer time to 9.39%. Therefore, the shared system bus can be kept as free as possible, which in turn leads to increasing the potentialities of improvement on system performance. Furthermore, this data transfer scheme also helps in accelerating the processing of shape coding(1).
MPEG-4 shape coding comprises context-based arithmetic encoding (CAE) as its centerpiece. Since the CAE algorithm has a complicated coding procedure and strong data dependency, it is hard to exploit its pipeline and p...
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MPEG-4 shape coding comprises context-based arithmetic encoding (CAE) as its centerpiece. Since the CAE algorithm has a complicated coding procedure and strong data dependency, it is hard to exploit its pipeline and parallel facilities. Furthermore, to encode multiple symbols within one, clock cycle, it needs to overcome the issues of extracting multiple contexts of these symbols, deriving multiple probabilities from these contexts, and performing multiple multiplicative range update operations. This paper presents an efficient pipelined multisymbol CAE architecture for real-time MPEG-4 shape encoding. The proposed design is based on the inherent characteristics of binary alpha blocks as well as the numerical properties of the probabilities indexed;by the contexts, and it is capable of encoding either a singe symbol, or multiple symbols within each clock cycle. To overcome the aforementioned issues under the consideration of the hardware cost and the critical path delay, only symbols with a particular set of contexts are chosen to be processed simultaneously within the same clock cycle. Theoretical analysis shows that the majority of symbols have contexts belonging to this particular set, and therefore CAE processing can be significantly accelerated. An example VLSI implementation of proposed architecture that encodes two symbols within each clock cycle without sacrificing the clock rate can achieve a speedup of 1.47 in comparison with traditional CAE architectures. This particular two-symbol design can support MPEG-4 Main Profile at levels 3 and 4 under extreme and typical conditions, respectively. When synthesized from Verilog RTL design by using TSMC 0.35-mum 1P4M CMOS technology, the design can run at 90 MHz.
In this article, we address the issue of operationally optimal shape encoding, which is a step in the direction of globally optimal resource allocation in object-oriented video. After an overview of shape-based coding...
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In this article, we address the issue of operationally optimal shape encoding, which is a step in the direction of globally optimal resource allocation in object-oriented video. After an overview of shape-based coding and algorithms, we define the problem mathematically, introduce the necessary notation, and then present the basic idea behind the proposed algorithms. We then discuss the constraints imposed on the code used to encode the approximation. We then introduce a definition of distortion that fits into the proposed framework and introduce the directed acyclic graph (DAG) formulation of the problem, which results in a fast solution approach. We also show how the DAG algorithm can be used to find the approximation with the minimum-maximum segment distortion for a given rate as well as to find the approximation with the smallest total distortion for a given rate. We then present experimental results and point out directions for future research.
shape is a popular way to define objects and shape coding is a key technique for object-based 3D video applications. In this paper, the issue of efficient shape coding for object-based 3D video applications is address...
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shape is a popular way to define objects and shape coding is a key technique for object-based 3D video applications. In this paper, the issue of efficient shape coding for object-based 3D video applications is addressed, and a novel contour-based and chain-represented scheme is proposed. For a given 3D shape video, contour extraction and preprocessing are first implemented followed by chain-based representation. Then, to achieve high coding efficiency, a chain-based prediction and compensation technique is developed based on joint motion-compensated prediction and disparity-compensated prediction to effectively exploit the intra-view temporal correlation and the inter-view spatial correlation. Experiments are conducted, and the results demonstrate that the proposed scheme is more efficient than the existing methods, including state-of-the-art methods.
This paper presents a fast binary motion estimation (BME) algorithm using diamond search pattern for MPEG-4 shape coding, which is the key technology for supporting the content-based video coding. Based on the propert...
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This paper presents a fast binary motion estimation (BME) algorithm using diamond search pattern for MPEG-4 shape coding, which is the key technology for supporting the content-based video coding. Based on the properties of binary shape information, a boundary mask for efficient search positions can be generated. Therefore, a large number of search points can be skipped. Simulation results show that our algorithm combined with diamond shaped zones takes equal bit rate in the same quality but reduces the number of search points marvelously in BME to 0.6% compared with full search algorithm, which is described in MPEG-4 verification mode. The proposed algorithm will reduce computational complexity of shape coding significantly and be suitable for real-time software and hardware applications of MPEG-4 shape coding.
The purpose of this paper it to explore the relationship between the rate-distortion characteristics of multiscale binary shape and Markov random field (MRF) parameters. For coding, it is important that the input para...
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The purpose of this paper it to explore the relationship between the rate-distortion characteristics of multiscale binary shape and Markov random field (MRF) parameters. For coding, it is important that the input parameters that will be used to define this relationship be able to distinguish between the same shape at different scales, as well as different shapes at the same scale. In this work, we consider an MRF model, referred to as the Chien model, which accounts for high-order spatial interactions among pixels. We propose to use the statistical moments of the Chien model as input to a neural network to accurately predict the rate and distortion of the binary shape when coded at various scales.
shape masks are used in object-based video coding, such as MPEG-4 part 2, to specify the boundaries of a video object. The term "binary shape" is used to describe shape masks where each pixel is either compl...
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shape masks are used in object-based video coding, such as MPEG-4 part 2, to specify the boundaries of a video object. The term "binary shape" is used to describe shape masks where each pixel is either completely inside the object or completely outside it, i.e., there is no blending of pixels at object boundaries. In this paper, we present a new lossless block-based coding algorithm for binary shapes that combines a quad-tree structure with context-based arithmetic coding. Experimental results demonstrate that this new approach provides a saving,in bits generated up to approximately 66% compared to the MPEG-4 binary shape coding algorithm.
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